VLE Calculations with Margules Equation

Organized by textbook: learncheme.com/
Uses VLE data at one liquid composition for a binary mixture and the two-parameter Margules model for activity coefficients to calculate VLE at another liquid composition. Made by faculty at the University of Colorado Boulder, Department of Chemical and Biological Engineering. Check out our Thermodynamics playlists: kzbin.info...

[@comicstwisted]

my greatest regret is going into chemical engineering

[@aldotovar9231]

fr

[@bks5493]

Why?

[@laurenrijo5857]

where do you get the equations for A12 and A21 @ 2:30 ? Is it just algebra from the two equations above?

[@sesshysayoyasha93]

Thanks a lot! This was very helpful!

[@echo0204]

I have a question: When is the saturation pressure on the modified Raoult's equation is changed to be standard fugacity? And why? THank you :)

[@yodawgoffdahook]

This video is a life saver

[@raphael4758]

Thanks a lot too! It helps me so much!

[@schuschnix5261]

hey,I have a question, there might be a better fitting video too, but this one comes pretty close actually. In my example it would also be gE via margules for an ethanol Water solution in a container.(in air 21%O2,79%N2) 1bar,25degrees. Molfractions are given..lets say 0,95 ethanol and rest water. Its not defined very well, but I believe the subquestion is:if you assume the room closed but big enough that it can fit the vaporpressures; what does the liquid look like after a while?(equilibrium) Edit:I have been told this is wrong since its not binary and I have to take O2 and N2 into account aswell, but that doesnt really help me Now here is the kicker, there is also air humidity in place, so how is that calculated? The above is pretty much all you are given, exept antoine for water and ethanol, which I will make up now but lets say ethanol 100mbar(pure so here 95mbar) water 30mbar(pure so here 1,5mbar) airhumitity 0,33=10mbar The problem is,even from a theorical standpoint I am not certain what happens. is water still evaporating aswell but just slower because ethanol has bigger vaporpressure and we already have some water up there too? Basically my question comes down to, what is the pressure in the gasphase. Additionally 2 questions for understanding:If there is enough water in a locked room, would it always go towards 100% relative humidity or is that not the case necessarily?Also,in reality would ethanol still evaporate if there is already 100%rel. humity or is that totally unrelated?

[@LearnChemE]

Sorry but I'm not sure of the question. The saturation pressure in the modified Raoult's law was not exchanged for the fugacity.

[@ChemistrySam]

the original problem conditions stated that y1 = 0.7. but when you solve at the end for y1+y2=1 using the parameters you find that y1=0.656.....

[@federicomarzocchi7169]

hi, i m trying to solve a problem in which i have to use margoules equations to calculate the molar fraction of a stream of ammonia and water at 25C and 5 bars. i have the A12 and the A21 parameters but no data about the molar fraction of liquid or vapor molar fraction. i only know that at the beginning of the process the water is all liquid and the ammonia is all gas do you have an idea about how to solve it?

[@ulviss]

Hello ) I just wonder that How you determined y1 is 0.7 ?

[@LearnChemE]

It is a given in the problem statement.

[@ulviss]

I mean the sum of mole fractions should be equal 1 but in this case it is 1.1@@LearnChemE

[@joanablourenco]

Hi! I would like to know how did you develop this video? What program do you use to project this image and do the anotation as you do. It is a digital pen? Thank you very much

[@LearnChemE]

We use Camtasia and a tablet PC with a stylus

[@joanablourenco]

Thank you!